DIAMONDUsed for ... drill bits in oil exploration and for slicing through concrete jewellery: naturally-made diamonds are of higher purity and very expensive!Because ... of its tetrahedral structure, diamond is one of the hardest known materials it has a high refractive index, light is reflected internally, so it sparkles all its electrons are used to create the bonding lattice, leaving none spare, it’s a poor conductor of electricity

GRAPHITE

FULLERENES

GRAPHENE

Allotropes of carbon

Until 1985 it was thought there were only two allotropes of carbon: diamond and graphite. But scientists thought they had detected the presence of another form of carbon in space. That mysterious new allotrope is C60, or buckminsterfullerene. Other fullerenes exist too, like C70, as well as ellipsoids and tubes.Used for ... drug delivery potentially – many researchers are currently working on thisBecause ... buckminsterfullerene’s intermolecular forces are weak, its melting point is low fullerenes have a sea of free electrons inside, they can conduct electricity

Graphene was a theoretical concept before it was isolated and studied in 2004 by Andre Geim and Konstantin Novoselov at the University of Manchester. They were awarded the Nobel prize in physics in 2010 for their discovery. It’s the thinnest, lightest, strongest, most stretchy material we’ve ever created.Used for ... solar cells that are both transparent and flexible smart windows that can control heat and light transmittance electronic displaysBecause ... of its spare electrons, graphene is an excellent conductor of electricity and heat

Used for ... pencil leads nuclear reactor cores, to stop or slow the nuclear reaction

Because ... its layer-like structure makes it soft and flaky, as a pencil it leaves marks on your paper so much energy is needed to break the covalent bonds, graphite is tough enough to be used in a nuclear reactor of its soup of spare electrons, it is a very good conductor of electricity

Diamond’s sublimation point. It’s so hard to change into a gas because of its tetrahedral structure. 1985

1 g

3600°C

Some elements are able to exist in different structural forms, known as allotropes. Carbon does this very well because of its ability to form bonds with other neighbouring carbon atoms – something called catenation. The way in which carbon atoms are connected to each other makes a big difference to the physical, chemical and electronic properties of the material.

Diamond has a tetrahedral structure.

Each carbon atom is connected to four other

carbon atoms by a covalent bond to form a

giant crystal lattice.

Buckminsterfullerene’s spherical structure

comprises 60 carbon atoms arranged as 10 hexagons and

12 pentagons.The same shape as a

football – which is why C60 is also sometimes called a

buckyball.

Each carbon atom is covalently bonded to three others, leaving one electron spare. This results in atoms arranged in flat layers of

hexagons, between which is a soup of free, delocalised electrons made up of the

spare electrons.

4027°C

Graphite’s sublimation point. That’s how much energy it takes to break its covalent bonds.

A team headed by Professor Sir Harry Kroto discovered and named C60, or buckminsterfullerene.

A single sheet of graphene the size of a football pitch would weigh less than 1 g!

Download thisPoster, fact sheet and activity for age range 14–16 from the Education in Chemistry website: rsc.li/3oDkjDa

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Think of graphene as a single layer extracted from graphite. In its

hexagonal lattice, each carbon atom is bonded

with three others, leaving a spare electron.

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